This invention relates generally to vacuum measurements, and more particularly to systems and methods for monitoring the integrity of a vacuum interrupter.
Generally, the operation of a vacuum interrupter for use with an electric power circuit deteriorates as the vacuum in the interrupter deteriorates, i.e. the pressure in the interrupter increases. When the vacuum deteriorates, the small contact spacing upon which operation of the interrupter depends, can no longer sustain the high voltage applied to the contacts. As a result, arcs and flash-overs are likely to occur, causing damage to the interrupter. Pressure within a vacuum interrupter may increase because of, for example, out-gassing from materials used for the interrupter or leakage of air into the interrupter.
In order to avoid the problems associated with loss of vacuum, it has been recognized that vacuum interrupters ought to be monitored for vacuum integrity. A simple, accurate, and non-intrusive system for performing this monitoring, however, has not been developed. There is a need, therefore, for an improved system and method for monitoring the integrity of vacuum interrupters. In particular, there is a need for a method and system for acoustic sensing of vacuum integrity.
Briefly, the present invention provides systems and methods for acoustic sensing of vacuum integrity. According to one aspect of the invention, there is provided a method for vacuum integrity sensing, comprising the following steps: injecting sonic signals into the body; detecting sonic signals reflected from the body; calculating a composite value from the sonic signals reflected from the body; and determining using said composite value if the body has an acceptable vacuum therein.
According to another aspect of the invention, there is provided a system for acoustic sensing of vacuum integrity comprising the following components: a transducer for sending sonic signals into a body; a receiver for receiving sonic signals reflected from the body; a signal processor for calculating a composite value from the sonic signals reflected from the body; and a processing unit for determining from said composite value whether the body has an acceptable vacuum therein.
The above-listed features of the present invention will be more fully set forth hereinafter.